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MG MGF Technical - air filter modifications?

i have a 99 mgf vvc and want to increase its performance.

I have looked at a K&N 57 filter as populer but 2 techies i spoke said "not on a vvc" use an induction kit like the Viper or the ITG

Problem I have is I still have 2 1/2 yrs warranty and dealer said any filter change will void it

So can I put the air filter system from the Trophy 160
on my vvc and if yes(engines exactle the same) will it (along with a 52mm throttle body) give me the same 10-15bhp hike as the viper or the ITG and still keep my warranty???
J HAM

I have the K&N 57 filter on my 98 VVC (as do many others) and it performs well and sounds even better. Not sure what your 'techies' have against the kit but it seems to be the most popular mod to any MGF and gives the perfomance increase you suggested - +15 bhp - or the specs say that any way.

<problem I have is I still have 2 1/2 yrs warranty and dealer said any filter change will void it>

Think you answered your own question - if you put the Trophy 160 air filter system in the VVC is this not a filter change ?????????

You need to talk to dealer if you don't want to void your warrenty - and get it in writing that any mod will not effect it. It seems you have asked the question and got your answer.

Remember - any mods and your insurance will be void too unless you tell them about it - this can be as costly as loosing your warrenty !!!

Keith
Keith Williams

John, is your VVC a MY2000 model? If so, then it is highly likely that you already have a Trophy 160/ TF spec airbox. If not, then you can fit one of these reasonably easily.

But will you have Trophy 160 power? Nope - the Trophy 160's head has been modified by MGR to give that kind of power...

What gain would you see fitting a Trophy 160 airbox to your car? Unfortunately, I can't tell you :o(

Best option IMO is to fit a K&N inside your present airbox, and upgrade to a full airfilter induction kit once the car is out of warranty...
Rob Bell

John
It is not quite so simple to fit the Trophy air box in place of the standard item. In addition to the air box you will need a new bracket which is only about 13. You will then have to remove the old resonator box. This is done either by dropping the sub frame or cutting it out and finding something to cover the gap lft behind the rear wheel. Once you have done this there is no going back to the original system.

I gave up on this and resorted to putting a K & N panel filter in the standard airbox and re-routing the cold air feed from the side air intake. This is purported to give approx 10 bhp increase, although I have not had it tested on the rolling road. See the page on 'Alternative Filter Options' on Rob's site.
http://www.mgf.ultimatemg.com/

This should not invalidate your warranty of alter your insurance premiums. It is easy to reverse if necessary.

Pete
Pete Fincher

Pete,

I've just fitted an ITG to my 2001 MPi and it doesn't have a resinator box. The existing air filter draws air though a short tube (about 500mm long)from the rear of the car. So if J Ham's car is an MY2000 then he won't have this problem
David Clelland

John,

I've (well Bob actually) fitted a K&N to my 2001 MPi today, I've spoken with my dealer and they said no warrenty problems. At one point I was going to get them to fit it at the last service, but the amount they quoted I felt was a bit steep.

I've also spoke to my insurance company as well, and they increased my premium by 25.

Neil.

Neil Sutton

"well Bob actually"

Neil, it was more a case of
"When I nod my head......you hit it"

;-)
Bob

Thanks everyone for the advice. I checked
out Rob site and think I'm going with the K&N57. I'm now off to talk to my dealer...
J HAM

The K&N is great on a VVC, and pound-per-bhp is better value than the ones your techies suggest!

But if it voids the warranty, then you might have to wait. My K&N didn't stop MGR paying for my new head and head gasket without complaint!
David Bainbridge

>>I've just fitted an ITG to my 2001 MPi and it doesn't have a resinator box. The existing air filter draws air though a short tube (about 500mm long)from the rear of the car.<<

That's the Trophy-style airbox I mentioned earlier DC! :o)

What's interesting is that although the new airbox design was standardised across the MGF range, no increase in power was ever claimed. Would have been easy publicity for MG at the time - so I guess that this means that the new airbox is not such a huge advantage over the original design...

The alternative filter design option that Pete mentions is very interesting - it's what Roger Parker and Bruno pioneered. I've not tried it myself, but I have no reason to doubt that it works as well as claimed! :o)
Rob Bell

Rob,

Having fitted the K&N yesterday, I replaced the Trophy-style airbox (including pipe), so I had to give it a little test-run. I was following Bob and at one point and he was able to pull away from me, this was something that never used to happen :-)

I even re-marked later that I felt the car didn't quite seem as quick. However the K&N is staying as I like the noise, and the grin is firmly fixed.

Got back for work this evening and had to go out for a little drive....

Neil.
Neil Sutton

>>I was following Bob and at one point and he was able to pull away from me, this was something that never used to happen<<

I wonder if the cold air intake pipes are okay? This is the single most common cause of a K&N failing to give the expected power.

Perhaps one of the pipes have come adrift or even the pipes are fractionally too close to the filter itself?
Rob Bell

Rob,

I checked the pipes at the bottom when I got home and they seemed ok, I will have a look at the top end next time I take the engine cover off.

It was only a very marginal thing anyway, I just dropped a gear, and was soon right back behind him.

Neil.
Neil Sutton

>> I even re-marked later that I felt the car didn't quite seem as quick. However the K&N is staying as I like the noise, and the grin is firmly fixed.

Isn't this exactly the problem with the K&N, thought the Trophy box was alot more efficient than the standard and even as good as the K&N.

I call this the 'K&N lag' hence the preference for enclosed induction systems.

Gaz (Hurricaned ...)
Gaz R

I agree with you actually Gaz; the improvement to low-end torque was very very noticeable when I enclosed my K&N inside the Rover820 airbox.
Rob Bell

Rob,

How easy was it to enclose the K&N ?

One thing I did manage to do on Sunday was hit the rev-limiter twice in about 10 miles once in 2nd once in third. In over 2 years of ownership it was the first time I had done it !!! With the K&N fitted the car does seem to rev "free-er".

Neil.
Neil Sutton

"It was only a very marginal thing anyway, I just dropped a gear, and was soon right back behind him."

Yeah, yeah, thing is Neil, I wasn't really trying at the time ;-)

Yer know...I'm not sure the airbox and pipe were that different from the ones I removed from my car. I think the phrase "Trophy-Style" might be confusing the plot.
Bob

Neil

You hit the rev limiter twice but the bikes still ripped past you and away :-)

Don't forget the centre lane on the A272 is "bikes only". If they wanted cars to use it they would have put the 2 white lines a bit further apart.
JohnP - Herts

Full test is this weekend in France and Belgium !!! Bob, if I spend all weekend trying to catch you up I will end with a headache cos your exhaust is bit loud :-)

"Don't forget the centre lane on the A272 is "bikes only". If they wanted cars to use it they would have put the 2 white lines a bit further apart" - I did wonder what those lines were all about ......

Neil Sutton

>>How easy was it to enclose the K&N ?<<

Pretty easy actually Neil. A couple of people have done this now (from the MG ZR, via the ZS to the MGF!) - and no two installations are the same! LOL But everyone seems pleased with the performance - which is good to know, as it means that I'm not going mad. Well, not that mad anyway... ;o)

>>One thing I did manage to do on Sunday was hit the rev-limiter twice in about 10 miles once in 2nd once in third. In over 2 years of ownership it was the first time I had done it !!! With the K&N fitted the car does seem to rev "free-er".<<

Yes, that's definitely one of the pleasures of the K&N - the car just feels as though it breaths more freely. My impression with the airbox is some of that top end 'zest' has gone, but is made up for in spades in terms of low- and mid- range torque.

It's alot quieter too - which is either a good or a bad thing, depending on your perspective...

Enjoy Spa guys! :o)
Rob Bell

This thread was discussed between 31/05/2003 and 04/06/2003

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